In Greek mythology, Circe (pronounced Cir'-za, Cir' xe or Cir'-zi) was a goddess living on the island of Aeaea.

Circe's father was Helios, the pre-Olympic titan of the Sun, and her mother was Perse, an Oceanid; she was sister of Aeetes, the king of Colchis and of Pasiphae and Aga. She transformed her enemies, or those who offended her, into animals through the use of magical potions. She was renowned for her knowledge of drugs and herbs.

In Homer's Odyssey, her home is described as a stone mansion standing in the middle of a clearing in a dense wood. Around the house prowled lions and wolves, the drugged victims of her magic; they were not dangerous, and fawned on all newcomers.

Circe worked at a huge loom. She invited Odysseus' crew to a feast, the food laced with one of her magical potions, and she turned them all into pigs with a wand after they gorged themselves on it. Only Eurylochus, suspecting treachery from the outset, escaped to warn Odysseus and the others who had stayed behind at the ships.

Odysseus set out to rescue his men, but was intercepted by Hermes and told to procure some of the herb moly to protect him from the same fate. When her magic failed he was able to force her to return his men to human form.

Circe fell in love with Odysseus, apologized for her wickedness, and convinced him and his crew to stay with her on Aeaea, where they were treated royally. After a year of rest and leisure, she assisted Oysseus in his quest to reach his home.